C2x

C2x is the informal name given to the next planned revision of the C programming language after C18/C17. It is being developed by the ISO/IEC JTC1/SC22/WG14 committee, which has historically overseen the C standard. The designation C2x signals the intended release timeline, with the exact year subject to the standardization process; once approved, the standard will be published as an ISO/IEC document (for example ISO/IEC 9899:202x or similar).

The C2x effort aims to address defects in earlier standards, clarify ambiguous rules, and introduce targeted improvements to the language and its standard library. The overarching goal is to enhance reliability, portability, and usability while preserving compatibility with existing C code and established compiler ecosystems. Changes are typically modest in scope to maintain broad cross‑platform support and predictable behavior across compilers.

Proposals and discussions within the WG14 community cover a range of topics, including potential updates to the preprocessor, refinements to the type system and semantics, and enhancements to library interfaces. Not all proposals are guaranteed to appear in the final standard; the process involves scrutiny, public drafts, and consensus before any feature is adopted.

As with prior C standards, the development of C2x influences compiler implementers and developer tooling. Early drafts are publicly discussed by the community, and compiler developers often track proposals to prepare compatible support. The final specification, once ratified, will define the official features, semantics, and library surface of the new C standard.